Punch press with adjustable ram



March 8, 1966 M. BURGETT PUNCH PRESS WITH ADJUSTABLE RAM 2 Sheets-Sheet1 Filed May 8, 1964 March 8, 1966 M. BURGETT PUNCH PRESS WITH ADJUSTABLERAM 2 Sheets-Sheet 2 Filed May 8, 1964 United States Patent 3,239,039PUNCH PRESS WITH ADJUSTABLE RAM Leslie M. Burgett, Rockford, Ill.,assignor to Whitney Metal Tool Company, Rockford, 11]., a corporation ofIllinois Filed May 8, 1964, Ser. No. 365,899 .7 Claims. (Cl. 19212) Thisinvention relates to punch presses and particularly to a punch presswith an adjustable ram.

An important object of this invention is to provide a punch press inwhich the ram can be manually adjusted to facilitate positioning of thepunch with respect to a preselected area or spot on the workpiece.

Another object of this invention is to provide a punch press having amanually adjustable ram to facilitate positioning of the punch withrespect to the workpiece, and selectively engageable power operatedmechanism for driving the punch through the remainder of a cycle, and inwhich the power operated mechanism will automatically return the ram tosubstantially the same initial position after each punching operation,independent of the previous manual adjustment of the ram.

Another object of this invention is to provide a punch press having amanually adjustable ram and a one revolution clutch for selectivelyestablishing a drive between the power operated flywheel and the ram,and which is so arranged as to minimize wear and damage to theinter-engaging members of the clutch.

Still another object of this invention is to provide a punch press witha manually adjustable ram, and which is of simple and economicalconstruction, and which is durable and reliable in use.

These, together with other objects and advantages of this invention willbe more readily understood by reference to the following detaileddescription when taken in connection with the accompanying drawingswherein:

FIG. 1 is a side elevational view of a punch press embodying the presentinvention;

FIG. 2 is a front elevational view thereof;

FIG. 3 is a fragmentary vertical sectional view taken on the plane 33 ofFIG. 2;

FIG. 4 is a transverse sectional view, taken on the plane 44 of FIG. 3;

FIGS. 5 and 6 are transverse sectional views taken on the plane 55 ofFIG. 3, and illustrating the parts in different moved positions; and

FIG. 7 is a fragmentary horizontal sectional view, taken on the planes77 of FIG. 5.

The punch press in general includes a frame 10 having a work support 11and a ram 12 reciprocable toward and away from the work support. Thepunch is mounted for reciprocation in guideways 13 on the frame and isoperatively connected through an eccentric means to a drive shaft 14. Inthe embodiment shown, the shaft 14 has an eccentric crank-15 on one endwhich is connected through a connecting rod 16 to the ram. Theconnecting rod has a pivotal connection at 17 to the ram and may, forexample, have a ball and socket connection (not shown). A punch or dieindicated at 18 is mounted on the ram as by a punch retainer 19. A dieshoe 21 is mounted on the support 11 and has means such as clamps 22 forclamping the workpiece W to the die shoe.

The punch press is power operated and includes a drive motor 25 which isconnected as through a pulley 26 and belts 27 to a flywheel 28. Themotor is continuously energized while the press is in operation tocontinuously rotate the flywheel 28 and, as shown, is operated under thecontrol of a switch 30 conveniently located alongside the frame 10.

A selectively operable drive mechanism is provided for establishing adrive between the flywheel 28 and the shaft 14 to drive the punchthrough a cycle. In order to facili- Patented Mar. 8, 1966 tatepositioning of the punch with respect to the workpiece W, the drivemechanism is so arranged as to permit manual adjustment of the ram 12downward to a level adjacent the workpiece, while the flywheel 28 isrotating and the drive mechanism is then operable to establish a drivingconnection from the flywheel to the shaft 14, to power operate the ramthrough the remainder of a cycle.

Referring now more specifically to FIGS. 37, the shaft 14 is rotatablysupported in bearings 32 on the frame 10 and a hand wheel 33 isnon-rotatably connected as by a key 34 to a stub 35 on the end of theshaft 14. The hand wheel 33 is disposed coaxial to the shaft and islocated at the end of the shaft adjacent the ram to enable manualturning of the shaft and the eccentric 15 for positioning of the ramwith respect to the workpiece. The selectively operable drive mechanismfor establishing a driving connection between the flywheel 28 and theshaft includes a driven member or hub 41 which is nonrotatably connectedas by a key 42 to the shaft. An annular drive member 43 extends aroundthe driven member and is rotatably supported as by anti-frictionbearings 44 on the shaft for rotation relative to the hub and shaftabout the axis of the latter. The flywheel 28 is supported for rotationrelative to the shaft and, as shown, has a bearing 46 which rotatablysupports the same on the end of the shaft. The flywheel is retained inposition on the shaft by a collar 47 and locking screw 48. A onerevolution clutch is provided for drivingly connecting the drive member43 to the flywheel to rotate the drive member through one revolutioneach time the clutch is operated. In the preferred embodimentillustrated, the clutch includes a first clutch member, advantageouslyin the form of a reciprocable clutch pin 51 which is mounted on thedrive member 43 for limited sliding movement relative thereto. A secondclutch member 52 is connected to the flywheel 28 for rotation therewithand, as shown, is attached to the flywheel by bolts 53. The clutchmember 52 has one or more recesses 54 therein which are adapted toreceive the end 51' of the clutch pin 51. The recesses define a shoulderor drive lug 54 at the side of the recess that trails during rotation ofthe flywheel, and which shoulder engages the end 51 of the drive pin torotate the drive member with the flywheel, when the drive pin is in itsengaged position. As shown in FIGS. 3 and 4, the drive pin is yieldablyurged into engaged position by a compression spring 56 interposedbetween a spring retainer 57 and the clutch pin 51. A clutch operatingcam 58 is disposed in the path of movement of a finger 59 on the clutchpin 51 and is arranged to move the clutch pin to its retracted position,when the drive member 43 approaches a preselected angular position. Asbest shown in FIGS. 3, 4, and 7, the clutch operating cam 58 has a camface 58' which is inclined to a radial plane to the shaft 14, and whichearns the clutch pin away from the clutch member 52. The clutchoperating cam is selectively movable in a plane disposed radially of theshaft out of engagement with the finger 59 on the clutch pin, in amanner described hereinafter, to effect selective engagement of theone-revolution clutch.

A lost-motion connection is provided between the drive member 43 and thedriven member 41 to enable manual turning of the shaft through a part ofa revolution for positioning of the ram and punch with respect to theworkpiece. As best shown in FIGS. 5-7, the drive member 43 has agenerally cylindrical bore 43 and a drive lug 61 is mounted on the drivemember and extends inwardly of the bore. The drive lug is preferably inthe form of an elongated bar which is mounted in the recess in the drivemember and is retained in position therein by a fastener 62. The drivenmember 41 is turnable relative to the drive member and has an outwardlyextending lug 64 defining a shoulder 64' disposed in the path ofrotation of the drive lug 61. The angular width of the drive lug 61 andthe driven lug 64 are selected so as to enable manual turning of theshaft 14 relative to the drive member 43 through approximately 180.Thus, the shaft can be turned approximately 180 from the position shownin FIG. 5 before the shoulder 64" on the driven lug engages the shoulder61" on the drive lug. As is apparent, the lugs 61 and 64 can be formedintegrally with the respective members 43 and 41 or may be formedseparate from the members and secured thereto. The clutch mechanism ispreferably so arranged as to stop the shaft 14 with the eccentric 15near upper dead center, and the shaft 14 is manually turnable by thehand wheel 33 to lower the ram to a position adjacent the workpiece formore accurate positioning of the punch with relation to the prescribedarea or spot on the workpiece. As the shaft is manually turned, theshoulder 64' on the driven lug moves away from the shoulder 61' on thedrive lug, as shown in FIG. 6. The clutch release cam 58 can then bewithdrawn from engagement with the finger 59 on the clutch pin 51 toestablish a driving connection between the flywheel and the drive member43. After an initial lost motion corresponding to the angle throughwhich the shaft was manually adjusted, the drive lug 61 will engage thedriven lug 64 to drive the shaft through the remainder of the revolutionof the drive member 43. As the latter approaches its initial positionshown in FIG. 3, the clutch release cam withdraws the clutch pin fromthe clutch member 52 and disengages the flywheel from the drive member.Brake bands 71 and 72 are provided around the drive member 43 and arounda drum 73 keyed to the shaft, to respectively retard rotation of thedrive member and shaft when the one revolution clutch is disengaged. Asshown, the brake bands are anchored against rotation by an anchor pin 75connected to the frame 10. The braking action of the brakes 71 and 72are individually adjustable and, as shown in FIG. 4, the brakingpressure applied by spring 76 is adjustable by means of a nut 77. Thebrake band 72 is preferably adjusted so as to stop rotation of the shaft14 when the eccentric 15 is near top dead center. The band 71 isadjusted so as to stop rotation of the drive member 43, after the clutchpin 51 is disengaged and is in a position such as shown in FIG. 4.

Any suitable mechanism may be provided for selectively moving the clutchrelease cam 58 out of engagement with the clutch pin. As shown in FIG.1, a foot treadle 81 is pivotally mounted on the frame and if connectedthrough a link 82 and lever 83 to a clutch operating rod 84. The clutchoperating rod is yieldably urged to a raised position by a compressionspring 85 which is interposed between a bracket 86 on the frame and astop 87 on the rod. A lower stop 88 is preferably provided on the rod tolimit upward movement of the same. The clutch operating mechanism shownin FIG. 4 is arranged so as to operate the clutch through only onerevolution, even if the treadle 81- is held in a depressed position. Asshown, the rod 84 is connected to a trip lever 91 which is pivotallymounted at 92 on the frame. A latch lever 93 is pivotally mounted at 94on the trip lever 91 and has a latch finger 95 engageable with a pin 96on the clutch release cam to draw the cam downwardly away from theclutch pin 51, when the lever 91 is depressed. The clutch release lever58 is yieldably urged to its engaged position as by a plunger 97 andspring 98 and a dog 99 is mounted on the drive member 43 and is arrangedto engage the latch lever 93 to disengage the latch lever from the pin96, after the drive member starts to rotate. Thus, the release cam 58 isautomatically returned to a position in the path of rotation of thefinger 59 on the clutch pin, independent of whether the treadle 81 isreleased. The latch lever 93 is yieldably urged toward its latchedposition by a plunger 101 and spring 102, and an adjustable stop 103 isprovided for limiting movement of the release cam 58 to its engagedposition.

From the foregoing, it is thought that the construction and operation ofthe punch will be readily understood. The clutch and brakes are soarranged as to normally stop the shaft 14 in a position in which theeccentric 15 is at or near top dead center, as shown in FIG. 3. The handwheel 33 can then be manually turned to lower the ram and position thepunch adjacent the workpiece, for more accurate location of the punchwith respect to the area to be punched. As the hand wheel is turned, theshoulder 64' on the driven member moves away from the shoulder 61' onthe drive member, as shown in FIG. 6. When the clutch release cam 58 isthereafter withdrawn from engagement with the clutch pin 51, the latteris moved under the bias of spring 56 into engagement with the clutchmember 52 and the drive member 43 is then rotated with the flywheel 28.After an initial lost motion corresponding to the angle between theshoulder 61 and 64', the drive lug 61 engages the driven lug 64 torotate the driven member 41 and shaft 14 with the drive member 43through the remainder of the revolution of the drive member. When thedrive member completes one revolution, the release cam 58 disengages theclutch pin 51 and the brakes 71 and 72 function to stop the drive memberand shaft.

As will be seen, the ram is manual-1y adjustable to any position and theclutch will then automatically operate to drive the ram through theremainder of the stroke and return it to the same initial position.Because of the lost motion between the drive lug 61 and driven lug 64,it is apparent that when the clutch pin 51 is initially engaged by therotating shoulder 54 on the clutch member 52, it is not subjected to ahigh impact or load since it is only necessary to overcome the inertiaof the drive member 43 at that time. After the lost motion determined bythe spacing between the shoulder 61' and 64 on the drive and drivenlugs, the drive member is drivingly connected to the driven member todrive the ram through the remainder of its stroke. At this portion ofthe cycle, however, the clutch is in its fully engaged position so thatdamage and Wear on the clutch pin 51" and lug 54 is minimized. Moreover,it will be seen that the driven member is effectively enclosed by thedrive member and that the outer surface of the drive member alsofunctions as a brake drum. In addition, the one revolution clutch iscarried by the drive member. This provides a simple and compact overallarrangement which is durable and rugged in use.

While I have shown and described a present preferred embodiment of theinvention, it is to be understood that the invention is not limitedthereto but may be otherwise variously embodied within the scope of thefollowing claims.

I claim:

1. In a punching machine including a frame, a reciprocable ram mountedon said frame, shaft means having an eccentric for reciprocating the ramas the shaft is rotated, power drive means including a flywheel disposedcoaxial to the shaft means and mounted for rotation relative to theshaft means, an adjustable clutch mechanism for selectively establishinga driving connection between the flywheel and the shaft means whilepermitting manual adjustment of the ram, said adjustable clutchmechanism including a drive member mounted for rotation relative to theshaft means and having a first drive lug thereon, a selectively operableone revolution clutch for drivingly connecting the drive member to theflywheel to rotate the drive member through one revolution, a drivenmember non-rotatably mounted on the shaft means and having a seconddrive lug disposed in the path of movement of said first lug on thedrive member, a hand wheel connected to the shaft means for manuallyturning the same through a portion of one revolution to adjust theposition of the same, said second drive l-ug being turn-. able with saidshaft means and away from said first drive lug when the shaft means ismanually turned thereby providing an angular lost motion between thelugs on the drive and driven members corresponding to the portion of therevolution through which the shaft means is manually turned, said firstlug being operative when the drive member is rotated to engage saidsecond lug after said angular lost motion to thereby drive the shaftmeans through the remainder of the revolution of the drive member.

2. The combination of claim 1 including first and second brake means forrespectively retarding rotation of said shaft means and said drivemember.

3. In a punching machine including a frame, a reciprocable ram mountedon said frame, shaft means having an eccentric for reciprocating the ramas the shaft means is rotated, power drive means including a flywheeldisposed coaxial to the shaft means and mounted for rotation relative tothe shaft means, an adjustable clutch mechanism for selectivelyestablishing a driving connection between the flywheel and the shaftmeans while permitting manual adjustment of the ram, said adjustableclutch mechanism including a driven member non-rotatably connected tothe shaft means and having an outwardly extending driven lug thereon, anannular drive member extending around the driven member and mounted forrotation relative to the shaft means, the drive member having aninwardly extending drive lug, a selectively operable one revolutionclutch for drivingly connecting the flywheel to the drive member torotate the drive member through one revolution, manually operable meansconnected to the shaft means for manually turning the same through aportion of one revolution to adjust the position of the ram, said drivenlug being turnable with said shaft means and away from said drive lugwhen the shaft means is manually turned thereby providing an angularlost motion between the drive and driven lugs corresponding to theportion of the revolution through which the shaft means is manuallyturned, said drive lug being operative when the drive member is rotatedto engage said driven lug after said angular lost motion to therebydrive the shaft means through the remainder of the revolution of thedrive member.

4. The combination of claim 3 wherein said drive member is rotatablysupported by bearings on said shaft means.

5. The combination of claim 3 including first and second brake means forrespectively retarding rotation of said shaft means and said drivemember.

6. The combination of claim 3 wherein said one revolution clutchincludes a first clutch member on the flywheel and a second clutchmember slidably mounted on said 6 drive member for movement into and outof engagement with the first clutch member.

7. In a punching machine including a frame, a reciprocable ram mountedon said frame, shaft means having an eccentric for reciprocating the ramas the shaft means is rotated, power drive means including a flywheeldisposed coaxial to the shaft means and mounted for rotation relative tothe shaft means, an adjustable clutch mechanism for selectivelyestablishing a driving connection between the flywheel and the shaftmeans while permitting manual adjustment of the ram-s, said adjustableclutch mechanism including a driven member non-rotatably connected tothe shaft means and having an outwardly extending driven lug thereon, anannular drive member extending around the driven member and mounted forrotation relative to the shaft means, the drive member having aninwardly extending drive lug, a one revolution clutch including a firstclutch member on said flywheel, a second clutch member slidably mountedon said drive member, means yieldably urging said second clutch memberinto engagement with said first clutch member, a clutch release cam formoving said second clutch member out of engagement with said firstclutch member when the drive member reaches a preselected position,manually operable means connected to said shaft means for manuallyturning the same through a portion of a revolution to adjust theposition of the ram, said driven l-ug being turnable with said shaftmeans away from said drive lug when the shaft means is manually turnedthereby providing an angular lost motion between the drive and drivenlugs corresponding to the portion of the revolution through which theshaft means is manually turned, selectively operable means for movingsaid release cam away from the second clutch member to thereby allow thesecond clutch member to engage the first clutch member and drive thedrive member through one revolution, said drive lug being operative whenthe drive member is rotated to engage the driven lug after said angularlost motion to thereby drive the shaft means through the remainder ofthe revolution of the drive member.

References Cited by the Examiner UNITED STATES PATENTS 1,686,584 10/1928Thomas 192-24 2,492,284 12/1949 Heim 192--12X DON A. WAITE, PrimaryExaminer.

BENJAMIN W. WYCHE III, Examiner.

1. IN A PUNCHING MACHINE INCLUDING A FRAME, A RECIPROCABLE RAM MOUNTEDON SAID FRAME, SHAFT MEANS HAVING AN ECCENTRIC FOR RECIPROCATING THE RAMAS THE SHAFT IS ROTATED, POWER DRIVE MEANS INCLUDING A FLYWHEEL DISPOSEDCOAXIAL TO THE SHAFT MEANS AND MOUNTED FOR ROTATION RELATIVE TO THESHAFT MEANS, AN ADJUSTABLE CLUTCH MECHANISM FOR SELECTIVELY ESTABLISHINGA DRIVING CONNECTION BETWEEN THE FLYWHEEL AND THE SHAFT MEANS WHILEPERMITTING MANUAL ADJUSTMENT OF THE RAM, SAID ADJUSTABLE CLUTCHMECHANISM INCLUDING A DRIVE MEMBER MOUNTED FOR ROTATION RELATIVE TO THESHAFT MEANS AND HAVING A FIRST DRIVE LUG THEREON, A SELECTIVELY OPERABLEONE REVOLUTION CLUTCH FOR DRIVINGLY CONNECTING THE DRIVE MEMBER TO THEFLYWHEEL TO ROTATE THE DRIVE MEMBER THROUGH ONE REVOLUTION, A DRIVENMEMBER NON-ROTATABLY MOUNTED ON THE SHAFT MEANS AND HAVING A SECONDDRIVE LUG DISPOSED IN THE PATH OF MOVEMENT OF SAID FIRST LUG ON THEDRIVE MEMBER, A HAND WHEEL CONNECTED TO THE SHAFT MEANS FOR MAUALLYTURNING THE SAME THROUGH A PORTION OF ONE REVOLUTION TO ADJUST THEPOSITION OF THE SAME, SAID SECOND DRIVE LUG BEING TURN-